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Louisiana Yards and Neighborhoods www.lsuagcenter.com/lyn Manage Yard Pests Responsibly Pesticide Consequences Synthetic chemical pesticides were introduced in the 1940s to control agricultural pests; unfortunately, there were some unexpected consequences… • Hazardous to humans • Residues in food • Environmental impacts • Pests becoming resistant • Expensive to use Cycle of Pesticide Dependency Many chemical pesticides are broad spectrum, killing not only targeted pests but beneficial organisms that serve as natural pest control systems. NO Natural Controls Indiscriminate mortality - pests and beneficials Dependence on chemical pesticides In the days following a pesticide treatment, pests reproduce faster than predatory insects. By killing off beneficial insects, pest populations flourish. Tolerance Some damage to plants is natural. Don’t strive for a pest-free yard; instead, decide on a realistic threshold of damage. What Is a Pest, Really? Pest: plant, animal or other organism that is out of place. Diseases, weeds, insects, reptiles, mammals, arthropods Of all insect species in the world, less than 1% considered pests Am I a pest? This depends on where I am feeding, in the yard or the butterfly garden. Aphids Honeydew CORNICALS • Piercing-sucking mouthparts allow aphid to feed on plant juices. • Causes stunting and curling on new terminal growth. • Excrete honeydew. Parasitized aphid mummy Watch for pinholes, indicating parasitism by a wasp. • 2 types: soft and armored scale. • Piercing-sucking mouthparts allow it to feed on plant juices. • Damage: chlorosis and leaf drop. • Soft scales excrete honeydew. Sooty mold (shown here) is a fungus that grows on honeydew excretions. Whiteflies • Piercing-sucking mouthparts allow it to feed on plant juices. • Infest lower leaf surfaces. • Damaged leaves appear spotted. • Sooty mold. • Transmit plant viruses. Immature whiteflies also damage plants. Spider Mites • Tiny, with 8 legs • Piercing-sucking • Mites, eggs, cast skins and webs visible with hand lens • Leaves appear stippled • High infestation rates lead to mite migration Thrips • Feed on flowers and young foliage • Found on the underside of leaf • Excrement is shiny-black • Transmit plant diseases • Damaged plants appear flecked or bleached • Cause leaf and flower distortions and bud drop Caterpillars • Larva of butterflies and moths. • Some have venomous spines. • Most are foliage feeders; some are borers. • 1 to 4 abdominal prolegs. Sawflies • Look like caterpillars • Foliage feeders • Proleg on each segment of the abdomen • One simple eye on each side of head Mole Cricket • Grass root feeders • Tunnel turf and dry out grass roots • 3 species in Louisiana • Front legs flattened and adapted for digging Chinch Bugs • Like hot, dry weather • Feed on many grasses; prefer St. Augustine grass • Piercing sucking mouthparts • Produce odor when crushed Red Imported Fire Ants • Infest 330,000,000 acres • Inflict painful sting • Build unsightly mounds • Can be beneficial • 60,000 to 100,000 per mound Environmental Stresses Many environmental effects mistakenly treated as pest problems • Drought • Nutrient deficiency • Variations in pH • Mechanical damage • Cold damage • Excessive water or fertilizer Herbicides injured this tomato plant. Integrated Pest Management (IPM) IPM is the coordinated use of pest and environmental information and available pest control methods… To prevent unacceptable levels of pest damage by the most economical means… With the least possible hazard to people, property and the environment. Principles of IPM Sustainable - using a resource so that the resource is not depleted or permanently damaged Prevention Cultural Practices Biological Methods Physical Methods Chemical Methods Prevention Our most sustainable pest control method involves avoiding the introduction of pests (into our country, state or yard). • Buy pest-free plants. • Select plants adapted to your yard. • Select resistant varieties. • Avoid notoriously problematic plants. • Properly install and maintain plants. Key Plant, Key Pest Some key plants are likely to be infested by key pests. For example, Azaleas are commonly infested by lacebugs, particularly if the azalea is planted in a sunny location. Scouting Monitor plants routinely to aid in early detection of an insect, disease or other problem. Look for: • Favorable conditions for pests • Signs and symptoms of pests – Damage to the plant – Pests (leaf spot, leaf curl, feeding) – Frass - insect excretions • Presence of natural enemies Cultural Practices We also can avoid problems with insects and diseases through proper design, installation and maintenance. Stressed plants are more susceptible to attack, like this Chinese Elm with crowded roots. Water Wisely • Water during the early morning, when leaves are already wet. • Avoid overhead irrigation of woody ornamentals. Many foliar diseases gain entry into plants through the water remaining on leaves. Biological Control The use of living organisms to control pests: • Predators • Parasites • Pathogens Lady beetles and their larvae feed on aphids and other soft-bodied insects. They are commercially available in bulk. Predators Predatory mite In general, predators are larger, faster, more aggressive and present in relatively fewer numbers than their prey. Bigeyed bugs are raised commercially to control whiteflies, spider mites, aphids, caterpillars & thrips. Assassin bug Predators • Can kill large numbers of prey • Generalists, rather than specialists • Often social creatures (wasps, ants) Wasps also can be pests if they congregate in the wrong places, like inside your home. Parasites • Very specialized • Often small • Look for: – A trail of bodies – Exit holes – Color changes Healthy aphids Parasitized aphids Pathogens • Naturally occurring insect diseases – Bacteria, fungi, viruses and protozoa • Often specific to host • Lag time - may take a few days to provide control Bacillus thuringiensis is a bacterium that kills caterpillars when ingested. Attract Beneficial Insects by: • Not using harmful pesticides • Providing food – Nectar and Pollen – Plant diversity • Providing shelter – Enhance vertical layers Food for Thought Many herbs and fragrant flowering plants attract natural enemies Gaillardia Clover Milkweeds Cilantro Goldenrod Dill Echinacea Fennel Sunflower Mustards Clover also fixes atmospheric nitrogen into a form available to other plants. As A Last Resort…. Sometimes, major pest damage reaches a level that is unacceptable to the observer. When all previous management efforts have been ineffective, individuals may wish to apply: • Physical methods • Chemical methods These are the least sustainable methods discussed because they are labor intensive, and often require repeated treatments. Physical Management • Remove pests by hand. • Remove infested parts. • Establish barriers to prevent pest access to plants. Yellow sticky paper attracts whiteflies and other insects. These traps help to monitor pest populations in greenhouses. Chemicals • Choose least harmful pesticides. – Use selective pesticides rather than broad spectrum killers. • Spot treat where pests are abundant, rather than the entire yard. • Follow pesticide label instructions carefully. Management Strategies • “Sap suckers”- (aphids, soft scales, mealybugs, whiteflies, spider mites) – Biological controls – Soaps and oils • Caterpillars – Bt • Plant chewers - (grasshoppers, beetles, leaf miners) – Use a proper insecticide if damage warrants action For More Information on IPM STRATEGIES Visit: www.lsuagcenter.com Features: newsletters, presentations, news releases, photo galleries, videos, publications, diagnostic clinic, listserv, links and more! Further Reading www.lsuagcenter.com/lyn • Louisiana Lawn Best Management Practices Pub.# 2940 • Insect Pest Management Guide • Turf Maintenance for Athletic Fields Pub.# 1989 • Managing Imported Fire Ants in Urban Areas Pub.# 2817 • Broadcast Baits for Fire Ant Control • Bugs, Bugs, Bugs Newsletter Further Reading (cont’d.) • Wildlife Newsletters: www.lsuagcenter.com/en/environment/wildlife/ louisiana+wildlife+news.htm • Plant Disease Control Guide • Turf Diseases • Weed Control Guide Thanks for Your Attention! Special thanks to the following reviewers for their valued contributions: FL114 ELM Design Team and the FYN Subcommittee Institute of Food and Agricultural Sciences, UF Agriculture Education and Communication Department Environmental Horticulture Department Entomology and Nematology Department Soil and Water Sciences Department Florida Cooperative Extension Service in: Alachua, Broward, Clay, Hillsborough, Lake, Miami-Dade, Orange, Pinellas, Sarasota and Volusia Counties Florida Organics Recycling Center for Excellence The Center For Wetlands, UF United States Department of Agriculture FL Department of Agriculture and Consumer Sciences: Division of Plant Industry Louisiana Yards and Neighborhoods www.lsuagcenter.com/lyn Manage Yard Pests Responsibly